Segment Information - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Net Sales	$ 285,814	$ 262,655	$ 535,253	$ 490,072
Renewable Energy and Conservation
Disaggregation of Revenue [Line Items]
Net Sales	98,259	76,004	194,756	144,841
Residential Products
Disaggregation of Revenue [Line Items]
Net Sales	139,472	130,433	242,891	234,142
Industrial and Infrastructure Products
Disaggregation of Revenue [Line Items]
Net Sales	48,083	56,218	97,606	111,089
Point in Time
Disaggregation of Revenue [Line Items]
Net Sales	187,883	184,350	344,297	339,819
Point in Time | Renewable Energy and Conservation
Disaggregation of Revenue [Line Items]
Net Sales	12,416	8,469	27,004	15,759
Point in Time | Residential Products
Disaggregation of Revenue [Line Items]
Net Sales	138,288	129,566	240,619	232,458
Point in Time | Industrial and Infrastructure Products
Disaggregation of Revenue [Line Items]
Net Sales	37,179	46,315	76,674	91,602
Over Time
Disaggregation of Revenue [Line Items]
Net Sales	97,931	78,305	190,956	150,253
Over Time | Renewable Energy and Conservation
Disaggregation of Revenue [Line Items]
Net Sales	85,843	67,535	167,752	129,082
Over Time | Residential Products
Disaggregation of Revenue [Line Items]
Net Sales	1,184	867	2,272	1,684
Over Time | Industrial and Infrastructure Products
Disaggregation of Revenue [Line Items]
Net Sales	$ 10,904	$ 9,903	$ 20,932	$ 19,487